Energy-translating device



Sept. 20, 1932. J. D. SEABERT 1,877,992

ENERGY TRANSLATING DEVICE Filed Sept. 6, 1930 INVENTOR JahnDSeQbertATTfDRNEY Patented Sept, 20, 1932 were. s

ENnaeY-rnAnsL'A'rme nnvron Application filed September 6,}1930'. Serialno. 480,174.

My invention relates to energy-translating current at audio frequencies.More particularly, my invention relates to speakers of the cone type andimprovements therein for obtaining more efficient reproduction of soundwaves.

. In the analysis of the operation of speakers of the cone type, moreparticularly, the diaphragm element, it has been found that, at thehigher audio frequencies, the diaphragm does not vibrate as a piston butdoes vibrate in sections; that is, the Whole area of the diaphragm isnoteffective, Whereas, for an eiiicient reproduction of low-frequencysounds,

a radiator of large area must vibrate andwith all parts 111 phase. I Asthe frequency of the impressed current approaches that of the loweraudio frequencies, sectional vibration of the diaphragm becomes lesspronounced, and the tendency is for the diaphragm to vibrate more andmore in the nature of a piston, that is, the diaphragm tends graduallyto assume, but never completely, the characteristic of a unitary rigidstructure, as the frequency of the impressed Wave approaches the lowerend of the audio-frequency spectrum.

Insofar as I am acquainted with the prior art, because of the abovevibration characteristics assumed by cone diaphragm speakers, no successhas been obtained inthe radiation of sound of any considerable pressureat frequencies lower than approximately 80 cycles. In speakers of thepresent day construction, those which are capable of respond ing tofrequencies as low as 80 cycles are considered as having very goodfrequency-respouse characteristics, 1 fully and efficiently reproducethe full effect of instruments emitting notes or tones below 80 cycles,such as the bassof an orchestra or the longerpipes of an organ, it isessential that the speaker be made to respond faith- However. tosuccess- E E Marmara Ernst; or DAYTON, 0310, nssrenon To wnsmmenonsnELECTRIC a men- @UFACTUBING COMPANY, a oonronarrou on rnnnsyrvnnm havingadiameter of approximately 25 to 30 inches will be suitable for thepurpose. If a cone of this area were driven at its apex, according tocustomary practice, only the center portion of the cone would vibrate,and it would beno more eifective than possibly a cone having a diameterof 10 to 12inches. Consequently, merely increasing the size of the conediaphragm will not produce the results desired. f

It is,.accordingly, one object of myinvention to provide means forextending the lowfrequency response of an energy-translating device. Itis another object of my invention to provide means for producing aspeaker capable of responding to frequencies of the order of '25cycles.r l

, Another. object of my invention is to provide means, forcausing thediaphragm of a cone speaker to vibrate as a unit. V r

In theaccompanying drawing, I have disclosed three views of oneembodiment of my invention. 1 I

Figure I is a front View of my device ner, of associating the drivingunits with the diaphragm. l i

Fig. i is a view, in cross-section, along the line IV-JVof Fig. 1 p,Fig. 5 is a view,in cross-section, along the line VV. of Fig. 2.

Other objects of my invention will be dis closed in the followingdescription of my device, whentaken in conjunction with theabove-referred-to drawing. y

In order to obtain thepistonaction of a diaphragm at the low frequenciesand to prevent the diaphragm from vibratingsectionally, I have conceivedthe idea of dis-. tributing the drivingforceabout the surface of thediaphragminstead of concentrating it all at one point, such as the apexof the "cone diaphragm normally used in practice. To accomplish theabove result, I have divided the diaphragm into a plurality of section ad have distributed the driving force among the various sections of thediaphragm.

ing, the vibratory element 1 is shown as comprising a plurality ofrelatively small coneshaped sections 3, the edges-5 of which intersectin the form ofa portion of a hyperbola, as clearly illustrated in Figs.4 and 5. This particular construction, functioning as trusses to resistdistorting forces, adds materially to the strength and rigidity of thediaphragm. The diaphragm is, accordingly, mounted on'a frame by means ofa flexible edging of leather 7 or other suitable material. Associatedwith each section, at the apex thereof, is an individual driving unit 9.These driving units are connected electrically from the same source ofaudio-frequency current and are so connected as to operate in '20 timephase, thereby causing the associated sections of the diaphragm to alsooperate in the same manner. a

A frame or supportll, maintained in spacedrelationship to the diaphragmby 26 means of a plurality of bracket arms 13, is employed as a mountingfor supporting the driving units 9 in their respectivepositionswithregard to their associated-diaphragm sections.

R ferring more particularly to the draw- 7 said vibratory element, saiddriving units being apportioned among said sections.

4. An energy-translating device comprising a vibratory element having aplurality of intersecting sections, the intersections being of suchcharacter :as .to resist distorting forces applied to the vibratoryelement.

In testimony whereof, I have hereunto subscribed, my name this 27th dayof August,

JOHN D. SEABERT.

The whole assemblage 'may be B mounted upon a stand 15', whereby it maybe conveniently'moved from one place to another. r

The above-described energy translator" may be set into a bafile orhornin accordance p with present practice in order to realize the fullbenefit of the device.

Various changes may be madein the structure described by me ascomprising one embodlment of my inventlon. Any driving 40 unitofsuitable type may be employed as well as any shaped diaphragmso longas they possess the desiredcharacteristics.

Therefore, while I have described my invention in detail',I do notdesire to be limited to the details described except insofar 4 as isnecessitated by the prior art and the appended claims. 7

I claim as my inventionz. 1. An energy-translating device comprising avibratory element and means foractuating said element as a unit, saidmeans comprising a plurality of independent driving units eachassociated with a section of said ing a vibratory element having a.plurality of. sections {of substantially cone-shape and driving meanscomprising a plurality of lndependent driving units associated with

